TitleEffects of soybean trypsin inhibitor on hypopharyngeal gland protein content, total midgut protease activity and survival of the honey bee (Apis mellifera L.).
Publication TypeJournal Article
Year of Publication2005
AuthorsSagili, R, Pankiw, T, Zhu-Salzman, K
JournalJ Insect Physiol
Date Published2005 Sep
KeywordsAnimals, Bees, Diet, Digestive System, Dose-Response Relationship, Drug, Insect Proteins, Longevity, Peptide Hydrolases, Pollen, Trypsin Inhibitor, Bowman-Birk Soybean

Insecticidal properties of protease inhibitors have been established in transgenic plants. In the wake of continuous research and rapid development of protease inhibitors it is important to assess possible effects on beneficial insects like the honey bee (Apis mellifera L.). In this study, newly emerged caged bees were fed pollen diets containing three different concentrations (0.1%, 0.5% and 1% w:w) of soybean trypsin inhibitor (SBTI). Hypopharyngeal gland protein content, total midgut proteolytic enzyme activity of these bees, and survival were measured. Bees fed 1% SBTI had significantly reduced hypopharyngeal gland protein content and midgut proteolytic enzyme activity. There were no significant differences between control, 0.1% and 0.5% SBTI treatments. Bees fed a diet containing 1% SBTI had the lowest survival, followed by 0.5% and 0.1%, over a 30-day period. We concluded that nurse bees fed a pollen diet containing at least 1% SBTI would be poor producers of larval food, potentially threatening colony growth and maintenance.

Alternate JournalJ. Insect Physiol.
PubMed ID15927200